Chainsaw Repair

A friend of mine may have just fried his 353. I don't know the damage, and I haven't seen it. The only report I've heard is "repair guy says compression is shot.  When asked for a probable cause, he says ethanol gas may be a prime suspect, he says a number of saws have come in with similar symptoms."  (I wonder if may have been run too lean?)

I'm trying to convince him to examine the possibility of replacing piston and rings, and maybe cylinder, depending on what it looks like. Neither of us have done this sort of work before, but he's fairly mechanically experienced. 

If it's not worth repairing, is the 545 about the closest replacement in the Husky line these days? He'd probably go for that over something in the 400 series (like a 450 or 455).  I can read the specs, I just want to make sure he's not stepping down in capability/durability.

If it helps for background:  He's used his 353 for about 5 years of "landowner"-type use (he cuts about 5 cords of firewood per year, and occasionally helps out others with their wood).  Mostly hardwoods (Beech, Ash, Maple, Oak), and mostly in the 4" to 10" diameter range (rarely up to 14", maybe more).  He's been happy with the 353, and doesn't mind being a bit patient on the rare occasions he gets into the larger stuff.  This will be his only saw.  He does appreciate a well-made saw, but price is a consideration. He may drool over the 562XP, but he's not likely to spring for it.  He a big Husky fan.  He might be convinced to step up to a 550, especially if he can find one on sale.  (I'm thinking the autotune feature may be a plus... I'm not sure how often he checks carb tuning, or even if he does it on his own or brings it to a dealer.)

Any thoughts?

Thanks, 660Magnum.  I'll recommend he take a close look at the 545.

BTW...Stochiometric ratio of Ethanol is 9:1.  It's Methanol that's down below 7:1.
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I've heard of several ways that ethanol might kill saws:

As you described... a slug of gas with higher ethanol content leans out the saw (could just be poorly mixed, or could be phase separation and the ethanol/water mix settled to the bottom of the tank)

Phase separation and the resulting corrosive ethanol/water mix attacking metal parts of the saw.

Ethanol attaches plastic/rubber components of the saw, some of which may allow air leaks, or otherwise lean out the saw through their deterioration.

A saw tuned for non-ethanol fuel, set a bit on the lean side, but not so much that it destroys the saw. Switching to E10 without retuning might lower the stochiometric ratio enough to cause a problem.  I'm not sure how likely this is, since switching from "straight" gas to E10 would only change the ratio from 14.6 down to about 14.0.  The difference would be even less noticeable if the fuel you started with was some oxygenated fuel other than E10 (MTBE, ETBE, LAME, etc).

Or it could just be that he never had the mixture checked, regardless of the fuel used and it finally caught up with him.

Just wondering does his 353 have the plastic intake clamp?

 I just bought a toasted 353 to rebuild myself, just because no need. I would at least look at rebuilding it anyways even if I bought a new one or  at least for learning experience rebuilding. Use used parts or good aftermarket and you can keep the cost down.

545 is a sweet saw and IMO could have replaced the 50cc 346 as well even though it was the 353 replacement.

I have a 545 and 550 on hand right now.

I forgot about the plastic clamp.  I had one on my Jonsered 2152.  I'll have to check his out. 

I know he bought this new more recently than 2007 (when I met him) probably in 2008 or 2009.  Unless he got one that had been sitting on someone's shelf for a while, isn't that new enough to have dodged the plastic clamp issue?

I had assumed the ones with the primer bulb had the metal clamp on the intake?

I didnt see mention of this 353 having primer bulb, did you?  I might have missed it.

The later 353's had the bigger bore too.

Tell me more on this subject and comparison of tops pistons etc..